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Different size tyres

Discussion in 'Gen 3 Prius Accessories and Modifications' started by zhutton, Sep 8, 2013.

  1. zhutton

    zhutton Junior Member

    Joined:
    May 27, 2012
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    Location:
    Staffordshire, UK
    Vehicle:
    2011 Prius
    Model:
    N/A
    Hello all,

    Apologies if this is already posted....

    I'm currently running 215/45/r17 tyres and I'm due a set of four (40k on the factory set)

    What difference would it make if I went for 215/50/r17 tyres?

    My car speedo is current about 4/5mph slow compared to my tomtom sat nav.

    Thanks in advance.

    Zakk
     
  2. vito.a

    vito.a Junior Member

    Joined:
    Aug 25, 2013
    52
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    Location:
    Tucson, AZ
    Vehicle:
    2010 Prius
    Model:
    IV
    The Prius OEM 195/65-15" tire usually reads about 1 mph fast on the speedometer at 60mph. The 17" wheel/tire combination with the OEM 215/45-17" tire is .4" shorter (1.4%) and usually reads about 2 mph fast at 60mph.

    You have some choices. You can try a 205/50-17" tire. It is .1" taller than the OEM 195/65-15" tire (.5" taller than your 215/45-17) and will read closer to actual.

    You can also try a 225/45-17" tire. It is the same size as the OEM 195/65-15 tire or .4" taller than your current tire. You will need to perform some measurements at full left and right turn lock to insure this 10mm wider tire will fit the front.

    Some folks will argue the wider tire may reduce MPG, but if you stay with a LRR (low rolling resistance) tire the difference will be negligible.

    Another possibility: I have not yet looked into, but on some cars the ECU can be adjusted for tire size to correct the speedometer.

    Let me know what you decide and how it works out?
     
  3. sarosh

    sarosh New Member

    Joined:
    Sep 22, 2020
    3
    3
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    Location:
    karachi
    Vehicle:
    2014 Prius
    Model:
    N/A
    Hey,
    Hope you guys are doing well.

    Can I install 215/55/r17 without any alteration to the car? Curently I am running stock 195/65/r15.
     
    GG707 likes this.